Farming crops with rocks to curb carbon emission

Sun Online Desk
23rd February, 2018 08:50:50

"This study has transformed how we think about managing our croplands for climate, food and soil security. It helps move the debate forward for an under-researched strategy of CO2 removal from the atmosphere - enhanced rock weathering - and highlights supplementary benefits for food and soils."

Prof David Beerling, who also heads the University's Leverhulme Centre for Climate Change Mitigation said, "The magnitude of future climate change could be moderated by immediately reducing the amount of CO2 entering the atmosphere as a result of energy generation.

Adopting strategies like this new research that actively remove CO2 from it can have a massive impact and be adapted very quickly."
The research examined the approach which involves amending soils with abundant crushed silicate rocks, like basalt, left over from ancient volcanic eruptions. As these minute rock grains dissolve chemically in soils, they take up carbon dioxide and release plant-essential nutrients.

Unlike other carbon removal strategies being considered, it doesn't compete for land used to grow food or increase the demand for freshwater. Other benefits of applying crushed silicate rocks include reducing the usage of agricultural fertilizers and pesticides, lowering the cost of food production, increasing the profitability of farms and reducing the barriers to uptake by the agricultural sector.

Arable farms already apply crushed rock in the form of limestone to reverse acidification of soils caused by farming practices, including the use of fertilizers.

Professor Stephen Long at the University of Illinois Champaign-Urbana, and co-author of the study said, "Our proposal is that changing the type of rock, and increasing the application rate, would do the same job as applying crushed limestone but help capture CO2 from the atmosphere, storing it in soils and eventually the oceans.

"Global warming is a problem that affects everyone on the planet. Scientists generally have done a poor job of getting across the point that the world must reduce emissions of greenhouse gases from fossil fuels and combine this with strategies for extracting carbon dioxide from the atmosphere to avoid a climate catastrophe," he added.

Professor James Hansen from the Earth Institute at Columbia University and co-author of the work, added: "Strategies for taking CO2 out of the atmosphere are now on the research agenda and we need realistic assessment of these strategies, what they might be able to deliver, and what the challenges are."

According to the Consultative Group on International Agricultural Research (CGIAR), a Washington-based global partnership of 15 research centres, reducing agriculture's carbon footprint is central to limiting climate change.

The University of Sheffield, a research university based in the city of Sheffield in South Yorkshire, England, was ranked 40th in the world's top 100 universities by the Global University Ranking Study in 2009, and was the Sunday Times University of the Year in 2001, reports UNB.